Sheet energy radiator



July 9, 1935.

C. H BRASELTON SHEET ENERGY RADIATOR Filed Aug. 19, 1930 INVENTOR Patented July 9, I935 UNITED STATES SHEET ENERGY RADIATOR Chester H. Braselton, New York, N.

to Sirian poration of Delaware Application August 19,

4 Claim.

This invention relates to devices and apparatus for producing a flat sheet of energized radiating area adapted for use either as a source of illumination or as a source of radiated energy for various other uses, including that of therepeutics, stimulation of plant growth, photography, signal transmission, and other uses.

One of the objects of my invention is to pro vide a radiating energy source which has an m enlarged area of distribution in contradistinction to radiating energy source confined to a point or along a line.

Another object of the invention is to provide a radiating energy source which may be utilized for illumination or other purposes, and which is adapted to conform to definite limited boundaries-so that in the case of illumination, for example, the apparatus may be used for advertising, communication or similar purposes.

An additional object is to provide an illuminatingdevice which may be so constructed as to provide a replaceable sign unit, such, for example, as the various letters of the alphabet.

Another object of the invention is involved' in the provision of radiating devices which may be utilized for color or other artistic or advertising efiects.

Various other objects will become evident on consideration of the-description of a specific embodiment of the invention hereinafter set forth, and in connection with the accompanying drawing, in which Fig. 1 is a view of a unit or lamp embodying one form of a sheet radiating device, which may be preferred;

Fig. 2 is a view of a modification of the radiating device or lamp; Fig. 3 is a plan section thereof; and Fig. 4 is a further modification showing a different configuration of the radiating structure. The present invention is intended to be used in connection with the energy radiator of the type described in my co-pending application, Serial No. 459,048 filed June 3, 1930. In this application I have described in detail a type of radiator wherein an electric discharge is made to form about a metallic conductor in a gaseous medium of such pressure as to confine the gas discharge path within prescribed limited areas adjacent 5 to the. metallic conductor.

In accordance with the invention of the application hereinabove mentioned, I utilize an envelope III of transparent or translucent material in whichvis contained an inert gas, such asa mixture of neon and argon, at a pressure of about Y., assignor Lamp Company, Newark, N. J., a cor- 1930, Serial No. 476,341 (Cl. 176-1) 200 mm. of mercury. Mounted on the stem H, within the envelope, are supports l2 and I3 which are adapted to engage the elliptical conductor M, which may be of refractory material such as tungsten. The supports also are preferably made of refractory material, such as tungsten, although nickel may be employed provided tungsten is utilized adjacent the emitter where the temperature is highest, and are spot-welded or otherwise attached to the emitting element I4.

The emitter I4 is coated throughout its length with a material which, when heated, emits electrons in greater density than ordinary metals or substances such as tungsten or copper. This coating, in its final form, may be of various component parts, but I have found satisfactory a mixture produced by combining barium carbonate, calcium carbonate, and barium nitrate with a binder of sufiicient nitrocellulose, dissolved in amyl acetate, to hold the coating on the-wire. The proportions of these substances were chosen as 40 grams of barium carbonate, 40 grams of calcium carbonate, and 8 grams of barium nitrate. This coating l5, of calcium and barium: carbonates, is secured to the tungsten base i6 of the emitter l4 and activated preferably by the means described in my co-pending application herelnabove referred to.

In accordance with this activation method, the mixture in the proportions above mentioned, is applied to a base in the shape of the filament, as indicated at H5 in Fig. 1. The filament is then appropriately mounted on the base supports I2 and l3 on the stem II, and the stem sealed in the bulb or envelope ill. The exhaust pump is then connected to the bulb and. an oven lowered thereupon to raise the temperature of the bulb and contents to about 400 C., or to as high a temperature as the envelope will stand without softening. Simultaneously electric current is passed through the filament which is thus heated to red heat of approximately 600 C. The heat and exhausting process is continued until there is no fluorescence when the high tension current is directed against the wall of the bulb, or in other words, until there is practically no more gas inside of the bulb. A vacuum of about one-half of a micron is an approximate limiting value.

The current is then increased through the filament so that the temperature thereof is slowly raised until it is about 800 degrees, or a bright red color, the exhaust operation being continued until the newly emitted gases are removed. The oven is then raised from the bulb and the filament heated to about 1200 (1., the pumping being continued until a high vacuum of one-half micron is again obtained.

The pump is then shut oil, the current turned off, and about one-half mm. of neon gas emitted to the bulb. The filament current is then turned on and gradually increased until a diffused glow completely fills the bulb. When the discharge is uniform throughout the bulb, which usually occurs in less than ten minutes, the so-called activating process for the filament coating is completed. Should white discharge spots appear on the filament or support rods, it is an indication that the gases or vapors within the bulb have not been completely removed, and the bulb is again exhausted and the whole process of activation repeated. When the activating process is finally complete, the filament temperature is raised for a moment to about 1400 C., and the pumping operation is again resumed to remove any undesirable gases which may have been thrown off during the activation process.

The filament circuit is then disconnected and the pump turned off and the appropriate amount of gas admitted to the bulb. In one form of my invention I utilize neon and argon gases in the relative amounts of 50 mm. of neon gas, and 150 mm. of argon. The bulb is then sealed off and a small quantity of magnesium flashed to absorb additional impurities, thus completing the process.

The device, as completed in accordance with the above process, may be energized by electric current, either alternating or direct, to cause formation of a halo or layer of highly active gases adjacent the coated conductor. The depth of this layer is dependent upon certain variables, such as the pressure of the gas and voltage applied to the bulb terminal, and where a single straight radiator is employed, the halo would be of approximately uniform cross-section and adjacent the length of coated material. In the form of my invention illustrated in Fig. 1, however, I have divided the filamentary coated conductor in the shape of an ellipse, the ends of which are attached to the supports l2 and 13. Consequently, the halo H, which has a highly energized gas area, tends to contract and diminish the unenergized space bounded by the ellipse, this contracting operation commencing at both ends and progressively moving toward the center of the ellipse until the inner elliptical area is completely energized, provided the dimensions of tht ellipse are not too large in proportion to the thickness of the halo orlayer on the conductor.

It is readily apparent that where a complete closed sheet is undesirable that the branches of the conductor may be sufliciently separated to maintain the partial unity of each conducting branch with possibly a sheet effect diverging the ends of the branches and open areas between each branch. It is also apparent that any number of electrically parallel circuits may be employed, depending upon the results desired.

Other monatomic gases such as krypton, helium, or metal vapors such as those of mercury, caesium, and rubidium may be used either alone or in combination with each other or with neon and argon.

Where the device is to be utilized for illumination, this construction provides a highly energized gaseous area in sheet form, which may be utilized for illumination at right angles to the plane of the sheet. By varying the contained gases a variety of light effects may be obtained which may be used for various light or other radiation eflects. For example, a mixture of argon, cesium, and neon with the argon predominating, produces a white light. Red is produced by neon and rubidium, with neon predominating. Yellow is produced by neon, mercury, and caesium, with neon predominating; blue, by a mixture of argon, mercury, and rubidium, with argon predominating; ultra-violet by a mixture of argon, mercury, and helium, with argon and mercury predominating; and infra-red by a mixture of helium and neon with mercury predominating. In all of these mixtures, at least five percent of helium is desirable, but not essential, as aiding the conductivity of the gas mixture. Where the device is used for energy radiation other than illumination, it is seen that the invention provides means for concentrating a large amount of energy normal to the energized sheet, this obviously having a number of practical applications.

As it is the tendency of the energized gas to develop into a sheet between closed boundaries, it is obvious that the operation is independent of the configuration of the bounding limits. These limits may take the shape of letters of the alphabet or any fanciful design or object which would adapt the invention for use in the field of advertising or communication of intelligence, as well as for illumination, or for the application of energy of selected frequency for a variety of specific purposes.

In Fig. 4 of the drawing is illustrated a possible variation in a star shape figure 20 having supporting contacts 2| and 22 by which electric current is introduced and conducted to the figure. 0n energization of the parallel conductors 23 and 24, the halo forms on the conductors and then spreads over the bounded area to form a starlike sheet of energy radiating gas.

In Fig. 2 of the drawing I have illustrated a modification of the invention. Within the envelope IO, and mounted on the stem I l, is a plurality of upstanding supports 32, 33, 34, and 35. Attached to the upper ends of these supports, as by spot-welding or by wrapping of the adjacent parts together, is a spiral radiator 35, formed of a tungsten base 31, on which the coating of radiating material 38 is similar to that described in connection with the radiator H of Fig. 1. Inspection of the drawing shows that the spiral 35 expands from its innermost end to its outer end.

Within the envelope I0 is a gas, preferably inert, such as argon and neon, as described in connection with the structure of Fig. 1.

The operation of the radiator, as above described and illustrated in Fig. 2, is as follows: When the potential is applied to the outer terminals of the device, the electric current passing through the filament 31 heats the coating 38 and causes the formation of an adjacent layer of ionized gases, in accordance with the principles described in connection with Fig. 1. At the point a, where adjacent portions of the spiral are closest together, the ionized gaseous atmosphere combines to form an active area in between these adjacent sections. This area tends to activate the gas intermediate the spiral segments toward the point b along the spiral, and causes progression of ionization to a point in the spiral where the ionized atmosphere is so attenuated that the energized area ceases to progress, thus forming a permanent or limiting point for the active ionized gases intermediate the adjacent portions of the spiral. A steady state having been arrived at, there is thus produced a spiral sheet of in the form of luminous energy, or in other for activated gas which functions to radiate energy dependent on the 5 and other variables chosen. Y

It is pointed out that when intermediate re-' gions between the adjacent turns of the spiral are activated, a dual path is provided for current flow, consisting of the metallic conductor 31 with its coating 38 and the energized atmosphere adjacent this conductor.

actual short-circuiting oi the metallic conductor along the axis'of the by means of the active gas, it is necessary that the degree of divergence of the spiral and the actual distances between adjacent portions of the spiral be such as to prevent short-circuiting effects. l

The breakdown potential of the gases used conductor should be, below the potential necessary to raise the coating on the conductor to such a temperature as to causeelectrons profusely. Where the coating to emit reference is made in the claims to electron emitting temperature, it is meant by this expression that the emission is sufliciently dense to permit functioning of the..discharge, and since the po tential when this condition is arrived at is reached at a point above the potential necessary for a breakdown discharge to occur along the conductor through the gases, the conditions are appropriate for the formation of the activated gas a layer hereinabove referred to.

" the solesource of the It should be mentioned further that while the coating of the conductor is described and illustrated as a part external to the conductor coil, it may also be applied internally of the coil as by forcing the material the coil interior and subsequently hardening, or by forming the material into a rod or pencil which may be positioned interior of the'coil.

In the claims the expression; an electronemitting coating on said tended to cover either of ticnings of the coating.

Various other modifications of the invention providing for a sheet radiator may be employed, such modifications, however, coming within the terms of the claims hereto appended.

I, Having thus described my invention, what I desire to claim is:

1. An electrical discharge device comprising an envelope, a divided conductor constituting discharge of the device within said envelope forming parallel conducting conductor is inthese alternative posipaths, a gas within said envelope surrounding In order to prevent an while in a plastic state into coating of material on said conductor containing alkaline earth metal as highly conductive in a limited region intermediate the segments of the divided conductor when the conductor is heated and a potential applied to the ends thereof whereby a sheet halo of substantial size is formed between said segments.

2. An electrical discharge device comprising an envelope, a filamentary divided conductor constituting the solesource of the discharge of the device within said envelope forming parallel conducting pat an electron emitting coating containing alkaline earth metal oxides on.said divided conductor, and an inert gas surrounding said conductor, the pressure of said gas being sufficient to confine the densely ionized portion thereof to the vicinity of said conductor when oxides to render said .said conductor 1s raised to electron emitting tem- 3. An electric lamp comprising an envelope, a filamentary helicallvwound conductor constituting the sole source of illumination of said lamp and forming a closed circuit conductor within said envelope, connecting conductors connected to separate points of said closed circuit conductor, a coating of electron emitting material containing oxides of the alkaline earth metals on said closed circuit conductor, and an ionizable gas containing argon and neon within said envelope having a. pressure such that the major ionization of said gas is confined to the area of gas enclosed by said closedconductor and immediately surrounding the same,

metal vapor and having a combined pressure preferably in excess of 150mm. of mercury and sustaining the formation of a substantial sheet form and that a sheet form halo of substantial area is formed within the halobetween the divided sections of the conductor when a current is passed through the conductor.

cnns'ran n. BRASELTON. 

